title: Optimized absolute testing method of shift-rotation.
abstract: The absolute testing method of shift-rotation that combines the traditional N-position method and Zernike polynomial fitting has been commonly employed in surface metrology. It preserves the high spatial frequency of the surface deviation with the N-position method to obtain the rotationally asymmetric surface deviation, but it suffers the kNθ order angular terms errors missed by the N-position method when it calculates the rotationally symmetric surface deviation with the Zernike rotationally symmetric polynomial fitting method. An optimized absolute testing method of shift-rotation is presented in this paper. It considers the missing kNθ order errors when the equations of the rotationally symmetric surface deviation are solved. As a result, it is more accurate than the traditional method. Experimental absolute results of spherical surfaces are given.
authors.forename: Weihong
authors.initials: W
authors.lastname: Song
authors.forename: Fan
authors.initials: F
authors.lastname: Wu
authors.forename: Xi
authors.initials: X
authors.lastname: Hou
authors.forename: Yongjian
authors.initials: Y
authors.lastname: Wan